Problem with Matlab mex

[bnash]

This isn't particularly an AT problem, but a general mex problem I'm having at the moment.
(cross-posted as a comment on this item at Matlab central:
https://www.mathworks.com/matlabcentral/answers/372419-why-does-matlab-not-recognize-my-xcode-9-installation-when-running-mex-setup)

I'm using Matlab 9.1.0.441655 on High Sierra. I upgraded XCode to 9.2.

When I run mex -setup I get this result

>> mex -setup -v
Verbose mode is on.
... Looking for compiler 'Xcode with Clang' ...
... Looking for environment variable 'DEVELOPER_DIR' ...No.
... Executing command 'xcode-select -print-path' ...Yes ('/Applications/Xcode.app/Contents/Developer').
... Looking for folder '/Applications/Xcode.app/Contents/Developer' ...Yes.
... Executing command 'which xcrun' ...Yes ('/usr/bin/xcrun').
... Looking for folder '/usr/bin' ...Yes.
... Executing command 'defaults read com.apple.dt.Xcode IDEXcodeVersionForAgreedToGMLicense' ...Yes ('4.5.2').
... Executing command '
agreed=4.5.2 
 if echo $agreed | grep -E '[\.\"]' >/dev/null; then 
 lhs=`expr "$agreed" : '\([0-9]*\)[\.].*'` 
  rhs=`expr "$agreed" : '[0-9]*[\.]\(.*\)$'` 
 if echo $rhs | grep -E '[\."]' >/dev/null; then 
 rhs=`expr "$rhs" : '\([0-9]*\)[\.].*'` 
 fi 
 if [ $lhs -gt 4 ] || ( [ $lhs -eq 4 ] && [ $rhs -ge 3 ] ); then 
 echo $agreed 
 else 
 exit 1
 fi 
 fi' ...Yes ('4.5.2').
... Executing command 'xcode-select -print-path' ...Yes ('/Applications/Xcode.app/Contents/Developer').
... Looking for folder '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.12.sdk' ...No.
... Looking for folder '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.11.sdk' ...No.
... Looking for folder '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.10.sdk' ...No.
... Looking for folder '/Applications/Xcode.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/MacOSX10.9.sdk' ...No.
... Executing command 'find /Applications/Xcode.app/Contents/Developer -name MacOSX10.12.sdk | egrep 'MacOSX10.12.sdk'' ...No.
... Executing command 'find $$ -name MacOSX10.11.sdk | egrep 'MacOSX10.11.sdk'' ...find: 26060: No such file or directory
No.
... Executing command 'find $$ -name MacOSX10.10.sdk | egrep 'MacOSX10.10.sdk'' ...find: 26064: No such file or directory
No.
... Executing command 'find $$ -name MacOSX10.9.sdk | egrep 'MacOSX10.9.sdk'' ...find: 26067: No such file or directory
No.
Did not find installed compiler 'Xcode with Clang'.
Error using mex
No supported compiler or SDK was found. For options, visit http://www.mathworks.com/support/compilers/R2016b/maci64.html.

[bnash]

Looks like I solved the problem, by adding references to MacOSX10.13.sdk
in /Applications/MATLAB_R2016b.app/bin/maci64/mexopts/lang_maci64.xml
and lang++_maci64.xml